Filter element with retaining surfaces, filter with a filter element and filter housing of a filter

ABSTRACT

A filter element ( 10 ) is provided with open filter body ( 16 ) of a filter medium ( 18 ). The filter element ( 10 ) has at least one longitudinal mating surface ( 40 ) which is directed with at least one direction component axially to an element axis ( 14 ) of the filter element ( 10 ) and which is in contact with a corresponding longitudinal mating surface of the filter housing ( 11 ) for securing the filter element ( 10 ) axially to the element axis ( 14 ). The filter element ( 10 ) has at least one transverse retaining surface ( 52 ) which is directed with at least one direction component across the element axis ( 14 ). The transverse retaining surface ( 52 ) is separated from the at least one longitudinal retaining surface ( 40 ) and may be in contact with a corresponding transverse mating surface ( 56 ) of the filter housing ( 11 ) for securing the filter element ( 10 ) across the element axis ( 14 ).

CROSS-REFERENCE TO RELATED APPLICATION

This application is a Continuation of U.S. application Ser. No.14/329,957, filed 13 Jul. 2014, which claims priority to German PatentApplication No. 10 2013 011 610.4, filed 12 Jul. 2013, the aforesaidGerman patent application and the US application being incorporated intheir entirety herein by reference.

TECHNICAL FIELD

The invention relates to a filter element, in particular a flat filterelement for installation in a filter housing of a filter for fluid, inparticular an air filter, in particular for an internal combustionengine, in particular for a motor vehicle, with a filter body or an openfilter bellows of a filter medium having an oncoming flow side and anoutgoing flow side for the fluid to be filtered, wherein the filterelement comprises at least one longitudinal retaining surface, which isdirected axially to an element axis of the filter element with at leastone direction component and can come in contact with a correspondinglongitudinal mating surface of the filter housing for retaining thefilter element axially to the element axis.

Furthermore, the invention relates to a filter for a fluid, inparticular an air filter, in particular for an internal combustionengine, in particular in a motor vehicle, having a filter housing, whichhas at least one inlet and at least one outlet for fluid and having atleast one filter element, in particular a flat filter element, inparticular a filter element according to the invention with filter body,in particular a filter body, made of a filter medium having an oncomingflow side and an outgoing flow side for the fluid to be filtered,wherein the filter element is disposed in the filter housing in such away that it separates at least one inlet from at least one outlet andwherein the filter element comprises at least one longitudinal retainingsurface which is directed axially to an element axis of the filterelement with at least one direction component and is in contact with acorresponding longitudinal mating surface of the filter housing forretaining the filter element axially to the element axis.

Furthermore, the invention relates to a filter housing of a filter forfluid, in particular a filter according to the invention, in particularan air filter, in particular for an internal combustion engine, inparticular in a motor vehicle which has at least one inlet and at leastone outlet for fluid, in which a filter element, in particular a filterelement according to the invention, in particular a flat filter elementcan be disposed such that it separates at least one inlet from at leastone outlet and wherein the housing axis has at least one longitudinalmating surface with respect to a housing axis, such that this matingsurface is directed with at least one direction component axially to thehousing axis and can come in contact axially with a correspondinglongitudinal retaining surface of the filter element for retaining thefilter element axially to the housing axis.

BACKGROUND

WO 2012/175438 A1 describes a filter device with a plate filter elementfor filtering fresh air for an internal combustion engine of a motorvehicle. The filter element has flat planar plate-shaped filter body,having an edge that is disposed peripherally and laterally as well asencompassing a cross section of the filter body through which the flowcan pass. The filter element is disposed in the interior of a filterhousing. The filter device is preferably an air filter device for amotor vehicle in particular.

The invention is based on the object of designing a filter element, afilter and a filter housing of the type defined above in which theretention and/or positioning of the filter element in the filter housingcan be improved. It should be possible in particular to improve guidanceof the filter element during installation in the filter housing, inparticular by simplifying it.

SUMMARY OF THE INVENTION

An object of the invention is to provide a filter element, a filter anda filter housing of the type defined above in which the retention and/orpositioning of the filter element in the filter housing can be improved.It should be possible in particular to improve guidance of the filterelement during installation in the filter housing, in particular bysimplifying it.

This object is achieved according to the invention with the filterelement by the fact that the filter element comprises at least onetransverse retaining surface which is directed transversely to theelement axis with at least one direction component, this retainingsurface being separate from at least one longitudinal retaining surfaceand it can be in contact with the corresponding transverse matingsurface of the filter housing for retaining the filter elementtransversely to the element axis.

Thus, according to the invention, multiple retaining surfaces areprovided, which can support the filter element in different directionswith respect to the filter housing. If an imaginary X-Y-Z coordinatesystem is on the filter element to facilitate a description, such thatthe z axis of this coordinate system runs axially to the element axis,then the filter element is supported in the filter housing with at leastone longitudinal retaining surface in the direction of the z axis. Thefilter element is supported with at least one transverse retainingsurface transversely to the z axis, in particular in the direction ofthe x axis and/or in the direction of the y axis.

With at least one retaining surface, the filter element mayadvantageously be supported radially to the element axis, i.e., radiallyto the z axis.

At least one transverse retaining surface and/or the correspondingtransverse mating surface may advantageously be designed so that thefilter element can be supported throughout the entire X-Y plane. Thefilter element can be supported in all directions transversely to theelement axis in this way.

At least one transverse retaining surface may advantageously have a bendabout an imaginary axis of bending, which runs essentially parallel tothe z axis. The filter element can thus be supported and retainedaccordingly in the filter housing in different directions in the X-Yplane by means of at least one curved longitudinal retaining surface andat least one transverse retaining surface.

At least one transverse retaining surface and at least one longitudinalretaining surface are separated from one another according to theinvention. “Separated” in this context means that the transverseretaining surface and the longitudinal retaining surface are notdisposed directly side by side, in particular on a common retainingconfiguration, but they may be attached in particular to a common endbody of the filter element, so that they can be connected to one anothermechanically by means of the end body. Due to this separation, at leastone transverse retaining surface and at least one longitudinal retainingsurface can each be optimized with respect to their direction ofsupport. Optimal transfer of force may therefore occur between thefilter element and the filter housing.

Relatively large, in particular bulky and/or heavy, filter elementsand/or those that are extensive in at least one direction, in particularin the direction of the z axis, may also be secured and positioned in astable and reliable manner in the filter housing with this invention.This makes it possible in particular to reliably secure filter elementshaving pleated filter media, with deep pleats and/or variable pleatheights, in a filter housing.

At least one of the retaining surfaces, in particular a transverseretaining surface and at least one corresponding mating surface of thefilter housing may thus advantageously be adapted to one another, sothat they can the improve guidance of the filter housing element duringinstallation into and/or dismantling from the filter housing in at leastsome sections. The positioning of the filter element in the filterhousing can thereby be improved. The shape of at least one matingsurface of the filter housing may thus advantageously approach a planeparallel to the z axis. Two opposing mating surfaces may advantageouslyform a funnel-type retaining receptacle for corresponding retainingsurfaces of the filter element at least in part. The corresponding,mutually opposite retaining surfaces of the filter element may beinserted easily into the funnel-type retaining receptacle and guidedinto their end positions. Conversely, two retaining surfaces of thefilter element may also surround two mating surfaces of the filterhousing with a funnel-type shape accordingly.

At least one longitudinal retaining surface and/or at least onetransverse retaining surface may advantageously be designed so thatmechanical forces can be transferred reliably between the filter elementand the filter housing by means of this surface. In particular at leastone retaining surface may be stable accordingly.

At least one longitudinal retaining surface and/or at least onetransverse retaining surface may advantageously be designed so that theyallow a tolerant installation of the filter element in the filterhousing. Then the corresponding at least one retaining surface maypermit tolerance guidance and/or positioning and/or tolerant retention.At least one of the retaining surfaces, in particular a transverseretaining surface and/or the corresponding mating surfaces mayadvantageously have a flexible, in particular elastic design. An optimalguidance and/or positioning and/or retention, in particular in aposition-tolerant manner, of the filter element in the filter housingcan thus be made possible.

At least one longitudinal retaining surface and/or at least onetransverse retaining surface may advantageously be designed inaccordance with filter-specific requirements, in particular the requireddirections of support, directions of load and/or directions of vibrationin the filter and/or adapted to one another. Due to the use of multipleretaining surfaces, which can provide support in different directions,the adaptation to the filter-specific requirements can be improved, inparticular by simplification and optimization.

At least one longitudinal retaining surface and/or at least onetransverse retaining surface may advantageously be designed so that itcan implement a damping effect, in particular a vibration damping effectbetween the filter element and the filter housing. The filter elementcan be protected in particular from operations-induced vibrations inthis way. The service life of the filter element can be increased.Alternatively or additionally, the damping may have a positive effect onany noise production by the filter during operation. The damping mayadvantageously be achieved by means of flexible, in particular elasticretaining surfaces and/or mating surfaces.

The filter element may advantageously be suitable for filtering air. Itmay also be provided for filtering other types of fluids, in particulargases or liquids. Thus a corresponding filter element may also be usedfor filtering fuel, oil, water or urea solution in particular.

The filter element may advantageously be used with an internalcombustion engine in a motor vehicle.

The filter element may advantageously be disposed in an air filter of acommercial vehicle, in particular a truck, a bus, a construction sitevehicle or an agricultural machine. Such filter elements may be oflarger dimensions in comparison with filter elements for passengervehicles. However, the filter element may also be used in passengervehicles.

The invention may also be used outside of automotive engineering, inparticular in industrial motors. Use of the invention outside ofinternal combustion engines is also possible, in particular inautomotive engineering.

The filter element may advantageously be a flat filter element. Thefilter element may be flat or curved. The oncoming flow side and/or theoutgoing flow side of the filter body may be flat or curved. The filterelement may also be box-shaped.

The filter body may be approximately in the shape of a polyhedron, forexample. The filter body may advantageously be cube-shaped, cuboid,pyramidal, prismatic, wedge-shaped or the like. It is not necessary forall sides of the filter body to be flat. Some of the sides of the filterbody may also be curved. Opposing sides may run in parallel.Alternatively or additionally, they may also run obliquely or beotherwise not parallel to one another.

The element axis of the filter element may advantageously be parallel oraxial to the installation direction of the filter element in the filterhousing. The housing axis of the filter housing may advantageously beparallel or axial to the element axis and/or the direction ofinstallation of the filter element. The dismantling direction is usuallyopposite the installation direction. The element axis of the filterelement may advantageously be a central axis and/or an axis of symmetry.The element axis may advantageously intersect with the oncoming flowside and the outgoing flow side of the filter element. In the eventthere is a planar oncoming flow side and/or a planar outgoing flow side,the element axis and/or the installation direction may advantageouslyrun perpendicular to the oncoming flow side and/or the planar outgoingflow side.

The filter medium may be a filter paper, a filter nonwoven, a meltblownnonwoven, a woven fabric or some other type of filter medium suitablefor filtering fluid, in particular air. The filter medium mayadvantageously be pleatable.

Alternatively, the filter body may also comprise a fluid-permeablefilter foam, in particular an air-permeable filter foam. The filter bodymay be implemented as a solid block of such a filter foam.

In an advantageous embodiment, at least one transverse retaining surfacewith respect to the element axis may be at a distance axially from atleast one longitudinal retaining surface with respect to the elementaxis.

This makes it possible to reduce the risk of tilting of the filterelement in the filter housing when being guided in its position and/orduring operation of the filter.

In another advantageous embodiment, a position of at least a part of atleast one transverse retaining surface may be elastically variable inrelation to the filter body in particular.

A flexible restraint and/or guidance, in particular an elastic restraintand/or guidance may be provided in or on the housing by means of atleast one transverse retaining surface in this way. This makes itreadily possible to equalize the tolerance between the filter elementand the housing in particular. Furthermore, vibration damping can beimplemented easily in this way.

At least one variable section of at least one transverse retainingsurface may advantageously be movable transversely to the element axiswith at least one direction component.

A body section, in particular a component or a part having at least onetransverse retaining surface may advantageously be variable in its shapeand/or position in relation to the filter body in order to change theposition and/or shape of at least one section of at least one transverseretaining surface. The body section with at least one transverseretaining surface may advantageously comprise an elastic material or bemade of an elastic material.

A section carrying at least one transverse retaining surface mayadvantageously be made of or comprise a plastic, in particular anelastomer. A resilient effect and/or shape can be implemented easily byusing a plastic. A section comprising or carrying the transverse matingsurface of the filter housing may also be made of or comprise plastic. Aplastic-plastic support can be implemented easily in this way. Suchsupports can be easily and reliably varied elastically. The sectioncomprising and/or carrying at least one transverse retaining surfaceand/or the section comprising or carrying the transverse mating surfacemay advantageously comprise or be made of elastomer. The elasticity ofthe support can be improved in this way.

At least one plastic element, in particular a foam element, mayadvantageously be glued to the filter body or optionally at least oneend body, which may comprise and/or carry at least one transverseretaining surface. At least one contact element may advantageously actas a support body. In particular at least one plastic element may be astrip. At least one plastic element may advantageously be made of athixotropic material, in particular polyurethane (PUR).

Alternatively or additionally, the section comprising and/or supportingat least one transverse retaining surface may comprise or be made ofmetal. This section may advantageously have a resilient effect and/ordesign.

Flexible and/or spannable and/or movable geometries, which may compriseand/or carry at least one retaining surface, in particular a transverseretaining surface, may advantageously be implemented on the filterelement, optionally on an end body of the filter element. Correspondingreceptacle geometries, in particular grooves and/or ribs, mayadvantageously be implemented in and/or on the filter housing.Alternatively, the flexible and/or spannable and/or movable geometriesmay be on the housing side. The corresponding receptacle geometries maybe on the filter element in this case.

In an advantageous embodiment, at least one of the retaining surfacesmay be disposed on a corresponding retaining configuration.

At least one of the transverse retaining surfaces may advantageously bedisposed on at least one transverse retaining configuration. At leastone of the longitudinal retaining surfaces may advantageously bedisposed on at least one longitudinal retaining configuration.

At least one retaining configuration, in particular a transverseretaining configuration, may advantageously have a movable section, inparticular an elastically movable and/or deformable section. Thissection may advantageously comprise and/or carry at least one transverseretaining surface.

At least one retaining configuration, in particular a transverseretaining configuration, may be connected to the filter body of thefilter element, either directly or indirectly. At least one retainingconfiguration may advantageously be connected to any end body of thefilter element.

A counterpart on the housing side corresponding to at least oneretaining configuration, in particular a transverse retainingconfiguration, for at least one transverse retaining configuration mayadvantageously be attached to the filter housing.

At least one retaining configuration may advantageously be connecteddirectly or indirectly to the filter body, in particular to an end body,if any, on the filter body or to the filter housing in a materiallybonded manner, in particular by means of adhesive bonding, weldingand/or injection molding or integral molding and/or in a form-fittingmanner, in particular by means of plugging, latching and/or tying and/orin a force-locking manner, in particular by means of clamping.

In another advantageous embodiment, at least one of the transverseretaining surfaces may be situated radially inside an imaginary cylinderwith respect to the element axis, whose radial outer peripheral side isdefined by the outer perimeter of the filter element in the direction ofthe element axis, in particular the direction of installation of thefilter element in the filter housing, as seen at the height of at leastone of the longitudinal retaining surfaces.

This makes it possible to prevent at least one transverse retainingsurface from protruding beyond at least one longitudinal retainingsurface in the direction of the x axis and/or the y axis. It is possiblein this way to achieve the result that the lateral extent of the filterelement is not increased further due to at least one transverseretaining surface.

At least one transverse retaining surface may advantageously be disposedin a region of the filter element in which the filter element is widerlaterally anyway, in particular radially to the installation directionand/or to the element axis, because of at least one longitudinalretaining configuration.

At least one of the transverse retaining configurations mayadvantageously be situated radially inside an imaginary cylinder whoseradial outer peripheral side is defined by the outside perimeter of thefilter element at the height of at least one of the longitudinalretaining configurations.

At least one of the transverse retaining surfaces, as seen in thedirection of the element axis, in particular in the installationdirection of the filter element in the filter housing, mayadvantageously be flush with at least one of the longitudinal retainingsurfaces, in particular at least one of the longitudinal retainingconfigurations. “Flush” in the sense of the invention means that aprojection of at least one transverse retaining surface in theinstallation direction, in particular in the direction of the elementaxis, is situated at least partially, preferably completely inside atleast one longitudinal retaining surface, in particular the longitudinalretaining configuration, or vice versa.

In another advantageous embodiment, at least one of the transverseretaining surfaces and at least one of the longitudinal retainingsurfaces may be disposed on the same peripheral side of the filterelement with respect to the element axis, in particular with respect tothe installation direction.

At least one of the transverse retaining surfaces and at least one ofthe longitudinal retaining surfaces may advantageously be contacted orintersected by a plane that is parallel to the element axis, inparticular the installation direction, or contains the element axis, inparticular the installation direction.

At least one of the transverse retaining surfaces and at least one ofthe longitudinal retaining surfaces may advantageously be contacted orintersected by an axis parallel to the element axis.

In another advantageous embodiment, at least one of the transverseretaining surfaces and at least one of the longitudinal retainingsurfaces may be disposed in the vicinity of opposite sides, inparticular end sides of the filter element, in particular axially withrespect to the element axis, in particular the installation direction.

“In the vicinity” in this context means that the distance between theretaining surfaces is much greater than the respective distances betweenthe retaining surfaces and the corresponding sides, in particular theoncoming flow side or the outgoing flow side of the filter element. Theretaining surfaces may also be disposed directly next to thecorresponding sides of the filter element.

At least one transverse retaining configuration and at least onelongitudinal retaining configuration may advantageously be disposed inthe vicinity of opposing sides of the filter element.

At least one of the transverse retaining surfaces may advantageously besituated in the vicinity of a front side of the filter element withrespect to the direction of installation of the filter element in thefilter housing. The front side of the filter element may advantageouslybe facing a housing bottom of the filter housing. The filter element caneasily be secured, guided and/or supported in the region of the housingbottom. The front side of the filter element may advantageously be theoutgoing flow side.

At least one of the longitudinal retaining surfaces may advantageouslybe situated in the vicinity of a rear side of the filter element. Therear side of the filter element may advantageously be the oncoming flowside.

At least two transverse retaining surfaces may advantageously bedisposed on the filter element. The filter element can be secured and/orsupported in several locations in this way. The filter element can thusbe uniformly secured and supported in the filter housing. In particularthe filter element can thus be guided uniformly in the filter housingduring installation and/or dismantling. The risk of tilting of thefilter element during installation or dismantling can be reduced in thisway. Even relatively heavy and/or large filter elements can bepositioned and secured easily and precisely in the filter housing.

At least two transverse retaining surfaces on opposite sides withrespect to a plane through the element axis, in particular the directionof installation, in particular the peripheral sides of the filterelement, may advantageously be disposed there. The filter element can besecured and/or supported uniformly on opposing sides in this way.

At least four transverse retaining surfaces may advantageously bedisposed so that they are on the periphery of the filter element withrespect to the element axis.

Two of the transverse retaining surfaces may advantageously be disposedin pairs.

In another advantageous embodiment, the filter medium may be pleated.The ratio between the active filter area and the design volume of thefilter body may be improved by pleating the filter medium.

The filter medium may be pleated in a zigzag configuration to form thefilter body. The filter media are not closed in filter elements, inparticular flat filter elements having open filter body. In other words,end pleats, like end edges, are not joined together. In contrast withthat, with hollow filter elements, in particular round filter elements,the filter media are shaped to form closed filter body, i.e., their endpleats are joined to one another. The end pleats are the two outermostpleats on opposite ends, in particular the longitudinal sides of thefilter body. The end edges are the two free edges of the filter medium,which run along the end pleats and border them on the end sides of thefilter body. The end edges of the filter body are the two other freeedges of the filter body, which extend between the end edges and runaccording to the pleat in the filter body. The pleated edges are theedges, along which the filter medium is pleated. In cube-shaped filterbody pleated in a zigzag pattern, the end edges and the pleated edgesare straight and run parallel to one another. The end edges run in azigzag pattern perpendicular to the end edges of the pleated edges. Theend edges each span one end edge of the filter body. With a pleatedfilter medium, the oncoming flow side of the filter body is spanned bythe pleated edges on the oncoming flow side. The outgoing flow side isspanned by the pleated edges of the filter body on the outgoing flowsides.

The filter body may advantageously have deep pleats. With filter bodythat are approximately cube-shaped, one speaks in particular of deeppleats when the pleat height is approximately at least as great as theextent in the direction of the pleated edges and/or in the directiontransversely to the pleated edges.

Varying pleat heights and/or pleat shapes may also be provided withinthe filter bellows. The pleat heights and/or pleat shapes may varywithin at least one of the pleats. Alternatively or additionally, thepleat heights and/or pleat shapes may also vary between the pleats, inparticular neighboring pleats. A curved shape of the oncoming flow sideand/or of the outgoing flow side may be implemented in this way. Thepleat heights at the center of the filter bellows in particular may besmaller than those in the region of the longitudinal sides.Alternatively, the filter bellows may also be graduated by varying thefilter heights appropriately. The filter bellows may thus be ofdifferent heights in the region of the end side.

In another advantageous embodiment, at least one end body, in particularan end disk, may be disposed on at least one peripheral side of thefilter body which extends between the oncoming flow side and theoutgoing flow side. The filter body and the entire filter element can bestabilized with at least one end body. Furthermore, the filter body maybe sealed in a particularly tight manner with at least one end body onthe corresponding side. Furthermore, at least one end body may serve asa connecting element or as a retaining element with which the filterelement can be positioned and held in a stable position in the filterhousing.

Corresponding end bodies may advantageously be disposed on multipleperipheral sides of the filter body. In this way the stability of thefilter element can be further improved.

One end body may advantageously be disposed on each of the opposingperipheral sides of the filter body. The end bodies may advantageouslybe situated on opposite sides of the filter body with respect to theinstallation direction of the filter element and/or the axis of theelement.

With a pleated filter medium, at least one end body may be situated onan end edge side of the filter body. At least one end body may beconnected tightly to the end edge side. At least one end body maytightly seal the end edge side of the filter body in this way.

Each end edge side of the filter body may advantageously be sealed withan end body.

At least one end body may advantageously be an end disk. An end disk isflat in its direction of extent in relation to the other directions ofextent. The space required by the end body and thus also the filterelement can be reduced as a whole in this way.

At least one end body, in particular the end disk, may be provided witha rib structure, with which the stability of the end body can beincreased.

A boundary shape of at least one end body may correspond to a boundaryshape of the filter body on the side on which at least one end body isdisposed. The shape of the end body may be adapted to a variation in theextent, in particular the height of the filter body, in particular avariation in the pleat heights.

At least one end body may advantageously be made of plastic or compriseplastic. Plastic may be elastic. At least one end body made of plasticmay have a mechanically damping effect in particular. Furthermore,plastic can be shaped easily, in particular by being cast or injectionmolded. The mobility, in particular flexibility of the support can befurther improved with an end body made of or comprising plastic.

At least one end body, in particular the end body made of plastic, mayadvantageously be joined to the filter body in a materially bondedmanner, in particular by welding or adhesive bonding, in a form-fittingmanner, in particular by means of a plug connection or a latchingconnection and/or in a force-locking manner, in particular by means of apress-fit connection or a clamp connection or in some other way.

In another advantageous embodiment, at least one of the retainingsurfaces may be connected in one piece to at least one end body inparticular. At least one retaining surface, in particular a transverseretaining surface, can be manufactured easily together with thecorresponding end body in this way, in particular by prefabrication. Atleast one end body with at least one retaining surface may easily beconnected to the filter medium. This may be performed advantageously inone operation.

At least one retaining surface and at least one end body mayadvantageously be joined to one another in one piece. With a one-piececonnection, the stability can be increased. Additional fasteningelements or additional assembly steps for joining at least one retainingsurface to at least one end body may then be omitted. A correspondingretaining configuration may advantageously be implemented for carryingor comprising at least one retaining surface on at least on end body.

At least one end body may easily and advantageously be made of plastictogether with at least one retaining surface, in particular by injectionmolding or casting.

At least one retaining surface may advantageously be integrated into theend body, in particular the end disk. In this way a space-saving andstable construction can be obtained.

Instead of being in one piece, at least one retaining surface may, as analternative, be designed as a separate part or may be connected directlyor indirectly to the end body on a separate part. The separate part mayform the corresponding retaining configuration at least in part. Theseparate part may advantageously be connected to at least one end body.Alternatively, the separate part may be connected directly to the filterbody.

At least one of the transverse retaining surfaces may advantageously beinside a region spanned by a projection of the end body in the directionof element axis, in particular the direction of installation, as seen inthe direction of installation. At least one handle element does not havea negative effect on a lateral extent of the filter element in this way.The lateral installation space of the filter element can be reduced inthis way.

At least one transverse retaining surface may advantageously be disposedon the outside of at least one end body facing away from the filterbody. At least one transverse retaining surface, in particular thetransverse retaining configuration, advantageously does not protrudebeyond the filter body on the oncoming flow side and the outgoing flowside. The extent of the filter element in the main direction of flowand/or in the direction of the axis of the element and/or in theinstallation direction can be reduced in this way.

Alternatively, at least one transverse retaining surface may be disposedon a front or rear side of the end body as seen in the direction of theelement axis. At least one transverse retaining surface may optionallybe disposed on a front or rear edge of the rear disk. At least onetransverse retaining surface therefore has little or no effect on thelateral extent of the filter element. The installation spacetransversely to the element axis can thus be reduced in this way.

A transverse retaining configuration comprising or supporting at leastone transverse retaining surface may advantageously protrude at leastpartially beyond an oncoming flow side or an outgoing flow side of thefilter body. At least one transverse retaining configuration mayadvantageously be situated upstream from the oncoming flow side ordownstream from the outgoing flow side in front of or behind the filterbody. At least one transverse retaining configuration may advantageouslyextend approximately parallel to a plane of the filter element in whichthe element axis is situated.

At least one of the retaining surfaces, in particular a transverseretaining surface may advantageously be disposed on the filter elementlaterally to the oncoming flow side and/or the outgoing flow side.Covering of the oncoming flow side and/or the outgoing flow side by atleast retaining surface can be reduced in this way. Interference in theflow of the filter element can thus be reduced.

In another advantageous embodiment, the filter element may have a filterelement holding device which may be connected directly or indirectly tothe filter body extending between the oncoming flow side and theoutgoing flow side along at least a part of the circumference of thefilter body and optionally having at least one retaining configurationthat protrudes away from the filter body transversely, in particularradially to an installation direction. The filter element can be securedeasily with the filter element holding device in a corresponding counterholding device of the filter housing. The filter element can bepositioned easily in the filter housing in this way. Due to the factthat the filter element retaining device extends at least along aportion of the circumference and has retaining configurations thatprotrude radially to the installation direction, axial positioning andretention in the filter housing are possible with respect to thedirection of installation and/or the element axis.

The filter element retaining device may advantageously be connected toat least one end body. The transfer of force from the filter housing tothe filter body and vice versa can be improved in this way.

The filter element may advantageously have a seal, which is closed onthe periphery with respect to the element axis. The seal may optionallybe positioned in or on at least one of the retaining configurations. Theseal may advantageously be positioned in or on the filter elementretaining device. The seal may advantageously also form the filterelement retaining device, at least in part.

In a configuration of at least one longitudinal retaining surface, inparticular at least one longitudinal retaining configuration in theregion of the end side on at least one end body, in particular the enddisk, a sealing line, in particular the seal may run around at least onelongitudinal retaining surface, in particular at least one longitudinalretaining configuration on the outside radially with respect to theelement axis. The sealing line may advantageously have bulges whichcorrespond to the position of at least one transverse retaining surface,in particular at least one retaining configuration, as seen in thedirection of the element axis. These bulges may advantageously alsosurround the longitudinal retaining surfaces at the same time, inparticular the longitudinal retaining configurations.

Furthermore, the object according to the invention is achieved by thefact that the filter element comprises at least one transverse retainingsurface, which is directed with at least one direction componenttransversely to the element axis, this surface being separated from atleast one longitudinal retaining surface and possibly being in contactwith a corresponding transverse mating surface of the filter housing forretaining the filter element transversely to the element axis.

Accordingly, the advantages and features described above in conjunctionwith the filter element according to the invention and its advantageousembodiments apply to the filter according to the invention and viceversa.

Furthermore, the object according to the invention is achieved with thefilter housing due to the fact that the filter housing comprises atleast one transverse mating surface, which is directed transversely tothe housing axis with at least one direction component, which isseparated from at least one longitudinal mating surface and may be incontact with a corresponding transverse retaining surface of the filterelement for retaining the filter element transversely to the housingaxis.

BRIEF DESCRIPTION OF THE DRAWINGS

Additional advantages, features and details of the invention are derivedfrom the following description, in which exemplary embodiments of theinvention are described in greater detail with reference to thedrawings. Those skilled in the art will also expediently considerindividually the features that are disclosed in combinations in thedrawings, the description and the claims, and will combine them intoother appropriate combinations. They show schematically:

FIG. 1 shows an isometric diagram of a detail of an air filter elementwith an air filter element according to a first exemplary embodiment,with end disks on opposing peripheral sides on which two transverseretaining cylinders which enter into corresponding transverse retainingreceptacles on the filter housing and two longitudinal retainingconfigurations are disposed;

FIG. 2 shows a detail view of the filter element from FIG. 1 in theregion of the transverse retaining cylinders;

FIG. 3 shows a detail view of the air filter from FIG. 1 in the regionof one of the transverse retaining cylinders and the correspondingtransverse retaining receptacle;

FIG. 4 shows an isometric diagram of a detail of an air filter with anair filter element according to a first exemplary embodiment, with twoalternative transverse retaining cylinders and a correspondingalternative transfer retaining receptacles;

FIG. 5 shows an isometric detail view of the air filter from FIG. 4 inthe region of one of the transverse retaining cylinders and thecorresponding transverse retaining receptacles;

FIG. 6 shows a section through the transverse retaining cylinder and thecorresponding retaining receptacle from FIG. 5;

FIG. 7 shows an isometric diagram of a detail of an air filter with anair filter element according to a third exemplary embodiment, with twolateral transverse retaining forks;

FIG. 8 shows a detail of a cross section of the air filter from FIG. 7in the region of one of the transverse retaining forks which enters intoa corresponding transverse retaining receptacle on the filter housingtransversely to the installation direction of the filter element;

FIG. 9 shows a detail of a cross section of an air filter with an airfilter element according to fourth exemplary embodiment in the region ofan alternative lateral transverse retaining fork, which surrounds andgrips a corresponding alternative transverse retaining receptacle on thefilter housing transversely to the installation direction;

FIG. 10 shows an isometric diagram of a detail of an air filter with anair filter element according to a fifth exemplary embodiment, with twolower transverse retaining forks which enter into correspondingtransverse retaining receptacles on the filter housing in theinstallation direction;

FIG. 11 shows a detail view of one of the transverse retaining forks andthe corresponding retaining receptacle from FIG. 10;

FIG. 12 shows an isometric diagram of a detail of an air filter with anair filter element according to a sixth exemplary embodiment, with twotransverse retaining straps which are in contact with correspondingtransverse retaining receptacles on the filter housing;

FIG. 13 shows a detail view of one of the transverse retaining straps onthe corresponding retaining receptacle from FIG. 12;

FIG. 14 shows an isometric detail diagram of an air filter with an airfilter element according to a seventh exemplary embodiment which issimilar to the air filter from FIGS. 12 and 13, in the region of twoalternative transverse retaining straps and the correspondingalternative transverse retaining receptacles;

FIG. 15 shows an isometric diagram of a detail of an air filter with anair filter element according to an eighth exemplary embodiment, with twotransverse retaining spring arms which are disposed approximatelycentrally on the end disks as seen in the direction of installation andextend essentially axially to the installation direction;

FIG. 16 shows a side view of the detail of the filter element from FIG.15;

FIG. 17 shows an isometric diagram of a detail of an air filter with anair filter element according to a ninth exemplary embodiment which issimilar to the air filter in FIGS. 15 and 16, with two alternativetransverse retaining spring arms which are disposed centrally on the enddisks and extend transversely to the installation direction;

FIG. 18 shows a bottom view of the detail of the filter element in FIG.17;

FIG. 19 shows an isometric diagram of a detail of an air filter with anair filter element according to a tenth exemplary embodiment, with twotransverse retaining clamps which are disposed approximately centrallyon the end disks with respect to the installation direction;

FIG. 20 shows a bottom view of the detail of the filter element in FIG.19;

FIG. 21 shows an isometric diagram of an air filter element according toan eleventh exemplary embodiment, with two transverse retaining stripswhich are disposed approximately centrally on the end disks with respectto the installation direction;

FIG. 22 shows an isometric diagram of a detail of an air filter with anair filter element according to a twelfth exemplary embodiment, with twotransverse retaining spring elements made of metal which are disposedapproximately centrally on the end disks with respect to theinstallation direction;

FIG. 23 shows a detail view of the filter element in FIG. 22 in theregion of one of the retaining spring elements.

The same parts in the figures are labeled with the same referencenumerals.

DETAILED DESCRIPTION OF THE INVENTION

FIGS. 1 to 3 show a detail of an air filter of an internal combustionengine of a motor vehicle according to a first exemplary embodiment indifferent perspectives. The air filter comprises a filter element 10,which is disposed in a filter housing 11 that can be opened, so that thefilter element can be replaced, and it separates an air inlet of thefilter housing 11 from an air outlet. The filter housing 11 is assembledfrom a housing pot and a housing cover. FIGS. 1 and 3 show only a detailof the housing pot of the filter housing 11, as described further below.The air filter serves to filter combustion air, which is supplied foroperation of the internal combustion engine.

The installation direction 12 of the filter element 10 in the housingpot runs parallel to an element axis 14 in the exemplary embodimentshown here. One housing axis of the filter housing 11, which is notshown here to facilitate understanding, runs coaxially with the elementaxis 14. The element axis 14, for example, runs parallel to the z axisof an X-Y-Z coordinate system, which is shown in FIG. 1 to simply thedescription.

The filter element 10 can be inserted into the housing pot through aninstallation opening.

The filter element 10 is designed as a flat filter element. The filterelement 10 comprises filter body 16 made of a filter medium 18 pleatedin a zigzag pattern, the body being approximately cube-shaped on theoutside. The filter medium 18 may be filter paper, filter nonwoven orsome other pleatable filter medium suitable for filtering air. Thefilter body 16 may also be made of an unpleated filter medium, forexample, a filter foam. The filter medium 18 is pleated along pleatededges 20. The pleated edges 20 run parallel to one another andperpendicular to the element axis 14. The pleat edges 20, for example,run parallel to an x axis of the X-Y-Z coordinate system.

FIGS. 1 and 2 show at the top, for example, one of the pleat edges 20 onthe oncoming flow side. The pleat heights 22 of the pleated filtermedium 18 extend parallel to the element axis 14, i.e., in the directionof the z axis. The axial height of the filter body 16 in the directionof the z axis with respect to the element axis 14 is greater than thewidth of the filter body 16 in the direction of the y axis. Thereforethese pleats can be described as deep.

End edge sides 26 of the filter body 16 are spanned by end edges of thefilter medium 18 which are concealed in FIGS. 1 and 2. The end edges ofthe filter medium 18 have an approximate zigzag shape. The end edgesides 26 are situated on radially opposite sides with respect to theelement axis 14. The end edge sides 26 run parallel to one another andperpendicular to an oncoming flow side 28 and an outgoing flow side 30.The oncoming flow side 28 and the outgoing flow side 30 are each spannedby the element axis 14 and the pleat edges 20 on the oncoming flow sideand/or the outgoing flow side respectively. The end edge sides 26connect two opposing longitudinal sides 24 of the filter body 16 thatare parallel to an X-Z plane and form with them the periphery of thefilter body 16.

The oncoming flow side 28, shown at the top of FIG. 1, is on the sidefacing the housing cover when the filter element 10 is installed.

The outgoing flow side 30, shown at the bottom of FIGS. 1 to 3, issituated on the side facing the pot bottom of the housing pot.

During operation of the filter element 10, the flow of air passesthrough the filter body 16 according to the present exemplary embodimentfrom the oncoming flow side 28 to the outgoing flow side 30. A maindirection of flow of the air through filter body 16 runs parallel to theinstallation direction 12 and to the element axis 14 in the presentexample. The flow can thus also pass through the filter body 16 in theopposite direction. In this case, the terms “oncoming flow side’ and“outgoing flow side” are reversed.

An end disk 32 is tightly connected to the end edges of the filterelement 18 on the end edge sides 26 of the filter body 16. The end disks32 are each made of plastic. The end disks 32 are approximatelyrectangular on the outside.

In the vicinity of its border on the oncoming flow side, each end disk32 has a longitudinal filter element retaining device 34. This filterelement retaining device 34 comprises a one-piece protrusion 36. Theprotrusion 36 extends peripherally with respect to the element axis 14.It extends outward from the filter body 16, as seen in the direction ofthe pleat edges 20, and approximately parallel to the border of the enddisk 32 on the oncoming flow side.

In the region of their ends, each of which faces the longitudinal sides24, the protrusions 36 each have an outwardly protruding longitudinalretaining configuration 38, as seen from the filter body 16. Thelongitudinal retaining configurations 38 each have a longitudinalretaining surface 40 on their side facing the oncoming flow side 28 andtheir side facing the outgoing flow side 30. The longitudinal retainingsurfaces 40 each extend approximately parallel to the X-Y plane.

With the help of the longitudinal filter element retaining device 34,the filter element 10 can be secured axially in the filter housing,i.e., longitudinally with respect to the installation direction 12 andthe element axis 14. The filter housing 11 therefore has correspondinglongitudinal mating surfaces (not shown in FIGS. 1 to 3) for thelongitudinal filter element retaining device 34.

A seal 42 which is designed as a profiled seal surrounds the filter body16 and the end disks 32 and/or the protrusions 36 and the longitudinalretaining configurations 38 are closed peripherally with respect to theelement axis 14. It is situated somewhat behind the pleat edges 20 onthe oncoming flow side as seen from the oncoming flow side 28.

Furthermore, the end disks 32 are each provided with reinforcing ribs44, which run in a grid pattern on their outsides facing away from thefilter body 16.

Two transverse retaining configurations 46 are disposed on therespective borders of the end disks 32 on the outgoing flow side facingthe outgoing flow side 30. The transverse retaining configurations 46are situated laterally in the vicinity of the respective longitudinalside 24. The transverse retaining configurations 46 are each intersectedby an imaginary plane, which is parallel to the X-Z plane runningthrough the corresponding longitudinal retaining configuration 38 whichis situated next to the same longitudinal side 24. The transverseretaining configurations 46 are situated on opposite sides of the filterelement 10 with respect to the X-Z plane. The transverse retainingconfigurations 46 of the two end disks 32 are situated on opposite sitesof the filter element 10 with respect to the Y-Z plane. The transverseretaining configurations 46 protrude beyond the filter body 16 on theoncoming flow side 28.

The transverse retaining configurations 46, shown in detail in FIG. 2,each have a retaining arm 48 and a retaining cylinder 50. The retainingarm 48 and the retaining cylinder 50 are each made of an elasticplastic. The retaining arm 48 is connected in one piece to the border ofthe end disk 32 on the outgoing closed side. It is curved in thedirection of the x axis toward the filter body 16 in a section facingthe border of the end disk 32. It thus extends into region of theoutgoing flow side 30. On its free end, the retaining arm 48 has a boltsection with an axis running parallel to the x axis. The retainingcylinder 50, which is therefore hollow on the inside, is attached to thebolt section. The imaginary axis of the retaining cylinder 50 extendsparallel to the x axis. The opposing peripheral sides of the retainingcylinder 50 which are on the outside radially and run tangentially tocorresponding imaginary planes parallel to the X-Z plane, formtransverse retaining surfaces 52 of the transverse retainingconfigurations 46.

The transverse retaining configurations 46 with the transverse retainingservice 52 are situated radially inside an imaginary cylinder withrespect to the element axis 14 and the installation direction 12, suchthat the peripheral side on the outside radially is defined by the outerperimeter of the filter element 10 in the direction of the element axis14 and the installation direction 12, as seen at the height of thelongitudinal retaining surfaces 40.

The filter housing 11 has a total of four transverse retainingreceptacles 54 for receiving the retaining cylinders 50. FIGS. 1 and 3show as examples two and one, respectively, of the transverse retainingreceptacles 54. The transverse retaining receptacles 54 are recesseswith a straight U-shaped profile as seen in the direction of the x axis.The open side of the “U” is situated on the side facing the installationopening of the filter housing 11. Transverse retaining receptacles 54there each open in a funnel shape. An imaginary longitudinal axis of therespective U-shaped profile runs parallel to the x axis. The U-shapedprofiles are each open on one side which faces an interior of the filterhousing 11 with respect the x axis. The insides of the side walls of thetransverse retaining receptacles 54 which face one another andcorrespond to the vertical legs of the “U” each formed transverse matingsurfaces 56.

A distance in the direction of the z axis between the longitudinalmating surface of the filter housing 11 with which the longitudinalretaining surface on the outgoing flow side of the longitudinalretaining configuration 38 of the filter element 10 (not shown in thefigures) can be in contact, and the center of the respective transversemating surface 56, as seen in the direction of the z axis, on the samelongitudinal side 24 corresponds to a distance between the longitudinalretaining surface on the outgoing flow side and the center of therespective transverse retaining surfaces 52 of the correspondingretaining cylinder 50, as seen in the direction of the z axis.

For installation in the filter housing 11, the filter element 10 isinserted through the installation opening into the housing pot with theoutgoing flow side 30 at the front. As soon as the retaining cylinders50 are at the entrances to the respective transverse retainingreceptacles 54, the retaining cylinders 50 are guided through the finalshape into the transverse retaining receptacles 54. The filter element10 is guided by means of the transverse retaining configurations 46 andthe transverse retaining receptacles 54 in the direction of the y axis,i.e., transversely with respect to the z axis, i.e., the direction ofinstallation 12. However, there is no guidance in the direction of the xaxis, so that in this direction there can be a position-tolerantinstallation.

Further movement of the filter element 10 in the installation direction12 is stopped as soon as the longitudinal retaining surfaces of thelongitudinal retaining configurations 38 of the filter element 10 on theoutgoing flow side are in contact with the corresponding longitudinalmating surfaces of the filter pot. The longitudinal mating surfaces forman axial stop, i.e., a longitudinal stop, with respect to the z axis.

The transverse retaining surfaces 54 of the retaining cylinders 50 aresituated approximately centrally on the respective transverse matingsurfaces 56 of the transverse retaining receptacles 54 in this positionof the filter element 10, as seen in the z axis. The transverseretaining surfaces 54 are supported on the respective transverse matingsurfaces in the direction of the y axis. The transverse retainingsurfaces 54 and the transverse mating surfaces 56 form a stop across,i.e., transversely to, the z axis and to the installation direction 12.

In the direction of the z axis and in the direction of the x axis, thetransverse retaining surfaces 54 and the transverse mating surfaces 56are able to move relative to one another. The positioning of the filterelement 10 on the sides of the transverse retaining configurations 56 istherefore positioned tolerant in the direction of the z axis and in thedirection of the x axis. Due to the elasticity of the retainingcylinders 50, a certain position tolerance is achieved in the directionof the y axis.

Next the housing cover is placed on the housing pot and the filterhousing 11 is closed. The housing cover comprises longitudinal matingsurfaces on the oncoming flow side which correspond to the longitudinalretaining surfaces 40 of the filter element 10 on the oncoming flow sideand are in contact with them when the housing cover is assembled. Thelongitudinal retaining configurations 38 and thus the filter element 10are secured longitudinally with respect to the z axis between therespective longitudinal mating surfaces on the oncoming closed side andthe longitudinal mating surfaces on the outgoing flow side.

Tilting and vibration of the filter element 10 in the filter housing 11are prevented or at least reduced by securing the filter element 10 withthe longitudinal filter element retaining device 34 on the oncoming flowside as well as with the transverse retaining configurations 46 onopposite sides on the outgoing flow side.

FIGS. 4 through 6 show an air filter with a filter element 10 accordingto a second exemplary embodiment. In contrast with the first exemplaryembodiment in FIGS. 1 to 3, in the second exemplary embodiment thetransverse retaining cylinders 50 are disposed between two retainingarms 148 instead of being on one retaining arm 48. The two retainingarms 148 are connected in one piece to the end disk 32. The bolt sectionon which the retaining cylinder 50 is situated extends between the tworetaining arms 148. The transverse retaining configurations 46 do notprotrude into the region of the outgoing flow side 30.

The transverse retaining receptacles 54 on the housing side are eachimplemented between two domes. The domes each extend in the direction ofthe z axis toward the installation opening of the filter housing 11. Thetransverse mating surfaces 56 are situated on the sides of the domefacing the other dome. The transverse mating surfaces 56 are each facingin the direction of the y axis.

The filter element 10 is supported against the filter housing 11 withthe transverse retaining configurations 46 in the direction of the yaxis.

FIGS. 7 and 8 show an air filter with a filter element 10 according to athird exemplary embodiment. In contrast with the first exemplaryembodiment, the transverse retaining configurations 46 in the thirdexemplary embodiment each have a retaining fork 250 instead of retainingcylinders 50. The retaining forks 250 are situated in the vicinity ofthe border of the end disk 32 on the outgoing flow side on the outsidefacing away from the filter body 16. The retaining forks 250 are flushwith one of the longitudinal retaining configurations 38 as seen in thedirection of the z axis.

Each of the retaining forces 250 has two legs whose centers are disposedin a plane parallel to the X-Y plane. The legs each extend outward fromthe outside of the end disk 32 facing away from the filter body 16 inthe direction of the x axis. The legs are elastically flexible in thedirection of the y axis, i.e., transversely. The oxides of the legsfacing away from the other leg in the direction of the y axis each formone of the transverse retaining surfaces 52. The transverse retainingsurfaces 52 are facing in the direction of the y axis.

The corresponding transverse retaining receptacles 54 on the sides ofthe filter housing 11 are implemented as U-shaped bulges in a peripheralwall of the filter pot facing the corresponding end disk 32. The sidewalls of the U-shaped bulge, which correspond to the legs of the “U” andform the transverse mating surfaces 58, each extend approximately in aplane parallel to the X-Z plane. The opening in the “U” is situated onthe side facing the end disk 32. The transverse mating surfaces 56 areeach directed in the direction of the y axis.

With the filter element 10 assembled, the legs of the retaining forks250 are inserted into the corresponding transverse retaining receptacles54. The transverse retaining surfaces 52 of the retaining forks 250 areeach in contact with one of the transverse mating surfaces 56 of thetransverse retaining receptacles 54.

The filter element 10 is supported against the filter housing 11 withthe transverse retaining configurations 46 in the direction of the yaxis.

FIG. 9 shows an air filter with a filter element 10 according to afourth exemplary embodiment. In contrast with the third exemplaryembodiment shown in FIGS. 7 and 8, the transverse retaining surfaces 52in the fourth exemplary embodiment are situated on the sides of the legsof the retaining forks 350 facing the respective other legs.

Instead of a bulge, the corresponding transverse retaining receptacles54 each have an elastic retaining web on sides of the filter housing 11.The retaining webs extend toward the interior of the filter housing 11approximately in a plane parallel to the X-Z plane. The transversemating surfaces 56 are situated on the opposite outsides of theretaining webs, as seen in the direction of the y axis. The transversemating surfaces 56 face in the direction of the y axis.

With the filter element 10 assembled, the legs of the retaining forks350 each extend around the corresponding retaining web of the transverseretaining receptacles 54. The transverse retaining surfaces 52 of theretaining forks 350 are each in contact with one of the transversemating surfaces 56 of the transverse retaining receptacles 54.

The filter element 10 is supported against the filter housing 11 withthe transverse retaining configurations 46 in the direction of the yaxis.

FIGS. 10 and 11 show an air filter with a filter element 10 according toa fifth exemplary embodiment. In contrast with the first exemplaryembodiment in FIGS. 1 and 3, the transverse retaining configurations 46each have a retaining fork 450. The retaining forks 450 are eachconnected in one piece to the order of the end disk 32 on the outgoingflow side. Each retaining fork 450 has two legs which extend essentiallyin the direction of the z axis away from the border on the outgoing flowside. The legs of the retaining forks 450 are elastically resilient inthe direction of the y axis. Each leg has a bend so that the retainingforks 450 each have a bulging shape on their opposite outer side in thedirection of the y axis. These outer sides of the legs form thetransverse retaining surfaces 52 of the transverse retainingconfigurations 46. The transverse retaining surfaces 52 are directedapproximately in the direction of the y axis.

The transverse retaining receptacles 54 are implemented in the same wayas the transverse retaining receptacles 54 in the first exemplaryembodiment in FIGS. 1 to 3.

With the filter element 10 assembled, the legs of the retaining forks450 are inserted into the corresponding transverse retaining receptacles54. Then each of the transverse retaining surfaces 52 of the retainingfork 450 is in contact with one of the transverse mating surfaces 56 ofthe transverse retaining receptacles 54.

The filter element 10 is supported against the filter housing 11together with the transverse retaining configurations 46 in thedirection of the y axis.

FIGS. 12 and 13 show an air filter with a filter element 10 according toa sixth exemplary embodiment. In contrast with the fifth exemplaryembodiment in FIGS. 10 and 11, each of the transverse retainingconfigurations 46 has a retaining strap 550 instead of the retainingforks 450. The retaining straps 550 are each connected in one piece tothe border of the end disk 32 on the outgoing flow side. They aresituated approximately in the extension of the end disk 32, as seen inthe direction of the z axis. The retaining straps 550 are elasticallyresilient in the direction of the x axis. The transverse retainingsurfaces 52 are each situated on the outside of the filter element 10facing away from the filter body 16.

In contrast with the previous exemplary embodiment, the transverseretaining surfaces 52 face approximately in the direction of the x axis.

The corresponding transverse retaining receptacles 54 on the side of thefilter housing 11 are implemented by corresponding retaining straps,which extend from the bottom of the housing pot in a plane approximatelyparallel to the Y-Z plane, toward the installation opening in thedirection of the z axis. The corresponding transverse mating surfaces 56are situated on the sides of the receiving straps, facing the interiorof the filter housing. The transverse mating surfaces 56 are directedessentially in the direction of the x axis. In the region of their endsfacing the installation opening, the receiving straps are beveled ontheir sides which have the respective transverse mating surface 56. Thebevels serve as a guide for the transverse retaining surfaces 52 of thetransverse retaining configurations 46 of the filter element 10 duringinstallation of the filter element 10.

During installation of the filter element 10, the retaining straps 550slide on the inside of the corresponding receiving straps of thetransverse retaining receptacles 54, where the inside is facing theelement axis 14. In the end position, the transverse retaining surfaces52 of the retaining straps 550 are each in contact with one of thetransverse mating surfaces 56 of the transverse retaining receptacles54.

The filter element 10 is supported against the filter housing 11 withthe transverse retaining configurations 46 in the direction of the xaxis.

FIG. 14 shows a seventh exemplary embodiment of a filter element 10. Incontrast with the sixth exemplary embodiment in FIGS. 12 and 13, thetransverse retaining surfaces 52 in the seventh exemplary embodiment aresituated on the insides of the retaining straps 550 facing the elementaxis 14. Accordingly, the transverse mating surfaces 56 are situated onthe outsides of the receiving straps of the transverse retainingreceptacles 54.

During installation of the filter element 10, the retaining straps 550slide on the outside of the receiving straps of the transverse retainingreceptacles 54. In the end position, the transverse retaining surfaces52 of the retaining straps 550 are each in contact with one of thetransverse mating surfaces 56 of the transverse retaining receptacles54.

The filter element 10 is supported on the filter housing 11 togetherwith the transverse retaining configurations 46 in the direction of thex axis.

FIGS. 15 and 16 show an air filter with a filter element 10 according toan eighth exemplary embodiment. In contrast with the first exemplaryembodiment, in the eighth exemplary embodiment, the transverse retainingconfigurations 46 each have a retaining spring arms 750. The retainingspring arms 750 are situated approximately centrally between the borderon the oncoming flow side and the border of the end disk 32 on theoutgoing flow side, as seen in the direction of the z axis, on theoutside facing away from the filter body 16. The retaining spring arms750 are flush with one of the longitudinal retaining configurations 38as seen in the direction of the z axis. The retaining spring arms 750are each elastically resilient in the direction of the x axis, i.e.,across or transversely to the z axis. The retaining spring arms 750 areeach connected in one piece to the end disk 32 on one end facing theborder on the outgoing flow side. The retaining spring arms 750 pointobliquely outward from the end disk 32 away from the filter body 16 tothe corresponding longitudinal retaining configuration 38, which issituated next to the same longitudinal side 24 of the filter element 10.The retaining spring arms 750 each have a convex curvature, as seen fromthe outside in the direction of the x axis toward the filter body. Animaginary axis of bending runs parallel to the y axis.

The outsides of the retaining spring arms 750 facing away from thefilter body 16 in the direction of the x axis each form a transverseretaining surface 52. The transverse retaining surfaces 52 are directedin the direction of the x axis.

The corresponding transverse retaining receptacles which are not shownin FIGS. 15 and 16, on the sides of the filter housing 11 havecorresponding transverse mating surfaces, which are directed essentiallyin the direction of the x axis.

With the filter element 10 assembled, the retaining spring arms 750 gripthe corresponding transverse retaining receptacles resiliently. Thetransverse retaining surfaces 52 of the retaining spring arms 750 areeach in contact with one or the transverse mating surfaces of thetransverse retaining receptacles. The transverse retaining surfaces 52press with the spring force of the retaining spring arms 750 against thecorresponding transverse mating surfaces in the direction of the x axis.The filter element 10 is positioned and held there in the direction ofthe x axis. The transverse retaining surfaces 52 and the transversemating surfaces can be moved relative to one another in the Y-Z plane.The tension and/or guidance of the filter element 10 by means of thetransverse retaining configurations 46 thus has position tolerance inthe direction of the z axis and in the direction of the y axis.

FIGS. 17 and 18 show a ninth exemplary embodiment of a filter element10. In contrast with the eighth exemplary embodiment in FIGS. 15 and 16,the retaining spring arms 850 are directed with the free ends toward oneanother on sides of one of the end disks 32.

FIGS. 19 and 20 show a tenth exemplary embodiment of a spring element10. As in the third exemplary embodiment from FIGS. 7 to 9, each of thetransverse retaining configurations 46 here has an elastically resilientretaining clamp 950. The transverse retaining configurations 46 aredisposed on the outside of the end disk 32, as seen in the direction ofthe z axis, approximately centrally between the border on the oncomingflow side and the border on the outgoing flow side. The transverseretaining configurations 46 with the corresponding longitudinalretaining configurations 38 are flush in the direction of the z axis inthe vicinity of the same longitudinal side 24.

Each retaining clamp 950 has two retaining webs, each extendingessentially in the direction of the z axis and in the direction of the xaxis. The retaining webs are symmetrical with respect to an imaginarymiddle plane of the retaining clamp 950 which extends parallel to theX-Z plane. Each retaining web has a concave curvature, as seen from theother retaining web in the direction of the y axis. The ends of theretaining webs facing the oncoming flow side 28 and the outgoing flowside 30 are situated at the same height, as seen in the direction of thez axis and are at a distance from one another in the direction of the yaxis. The retaining webs are elastically bendable in the direction ofthe y axis. The outsides of the retaining webs facing away from theother retaining web, respectively, in the direction of the y axis havetransverse retaining surfaces 52. The transverse retaining surfaces 52extend essentially in the direction of the x axis with a curveaccordingly and in the direction of the z axis. The transverse retainingsurfaces 52 are directed approximately in the direction of the y axis attheir center.

The corresponding transverse retaining receptacles (not shown in FIGS.19 and 20) on the sides of the filter housing 11 have correspondingtransverse mating surfaces, which are directed essentially in thedirection of the y axis.

With the filter element 10 assembled, the retaining webs of theretaining clamps 850 elastically grip the corresponding transverseretaining receptacles. The transverse retaining surfaces 52 of theretaining clamps 850 are each in contact with one of the transversemating surfaces of the transverse retaining receptacles. The transverseretaining surfaces 52 are supported on the corresponding transversemating surfaces in the direction of the y axis, i.e., transversely to oracross the z axis and the element axis 14. The filter element 10 ispositioned and secured there in the direction of the y axis. Thetransverse retaining surfaces 52 and the transverse mating surfaces aremovable relative to one another in the direction of the z axis and inthe direction of the x axis. Retention and/or guidance of the filterelement 10 by means of the transverse retaining configurations 46has/have extensive position tolerance of those in the X-Z plane.

FIG. 21 shows an air filter with a filter element 10 according to aneleventh exemplary embodiment. The eleventh exemplary embodiment differsfrom the tenth exemplary embodiment in FIGS. 19 and 20 in that thetransverse retaining configurations 46 each have an elastic retainingstrip 1050. The retaining strips 1050 are each approximately in theshape of a circular cylinder, which is divided in its length and whosebase surfaces have a spherical rounding. An imaginary axis of thecircular cylinder extends in parallel to the z axis and is situated onthe side facing the end disk 32. The outer peripheral side of theretaining strip 1050 facing away from the filter body 16 forms thetransverse retaining surface 52. The axis of the circular cylinder maybe referred to as the bending axis of the curved transverse retainingsurface 52.

The corresponding transverse retaining receptacles (not shown in FIG.21) on the sides of the filter housing 11 have transverse matingsurfaces corresponding to the transverse retaining surfaces 52. Thetransverse mating surfaces are curved according to the peripheral sidesof the retaining strips 1050, so that they form a type of channel toreceive the respective retaining strip 1050.

When the filter element 10 is assembled, the retaining strips 1050engage elastically in the corresponding transverse retainingreceptacles. The transverse retaining surfaces 52 are each in contactwith one of the transverse mating surfaces of the transverse retainingreceptacles. The transverse retaining surfaces 52 are supported on thecorresponding transverse mating surfaces in the X-Y plane, i.e.,transversely to or across the z axis and the element axis 14. The filterelement 10 is positioned and secured there in the X-Y plane. In thedirection of the z axis, the transverse retaining surfaces 52 and thetransverse mating surfaces are movable relative to one another.Retention and/or guidance of the filter element 10 by means of thetransverse retaining configurations 46 has/have position tolerance inthe direction of the z axis. Due to the elasticity of the retainingstrips 1050, a certain position tolerance is also achieved in the X-Yplane.

FIGS. 22 and 23 show an air filter with a filter element 10 according toa twelfth exemplary embodiment. In contrast with the eighth exemplaryembodiment in FIGS. 15 and 16, the transverse retaining configurations46 in the twelfth exemplary embodiment each have a retaining springelement 1150, which extends in the direction of the z axis. Theretaining spring elements 1150 are curved plate springs, which areclamped between two retaining webs under an elastic spring prestress.The retaining spring elements 1150 are preferably made of a materialhaving spring elasticity. The retaining webs are situated on oppositesides as seen in the direction of the z axis and are each connected inone piece to the end disk 32. The retaining spring elements 1150protrude beyond the retaining webs each with a bulgy section in thedirection of the x axis. The bulgy section forms the correspondingtransverse retaining surfaces 52. At their center, the transverseretaining surfaces 52 are directed in the direction of the x axis.

With the assembled filter element 10, the retaining spring elements 1150act elastically on the corresponding transverse retaining receptacles onthe side of the filter housing 11. The transverse retaining surfaces 52of the retaining spring elements 1150 are each in contact with acorresponding transverse mating surfaces of the transverse retainingreceptacles. The transverse retaining surfaces 52 are supported on thecorresponding transverse mating surfaces in the direction of the x axis,i.e., transversely to or across the z axis and the element axis 14. Thefilter element 10 is positioned and secured there in the direction ofthe x axis. The transverse retaining surfaces 52 and the transversemating surfaces are movable relative to one another in the Y-Z plane. Aretention and/or guidance of the filter element 10 by means of thetransverse retaining configurations 46 has/have a position tolerance inthe direction of the Y-Z plane.

Due to the elasticity of the retaining spring elements 1150, a certainposition tolerance is also achieved in the direction of the x axis.

What is claimed is:
 1. A filter element (10) configured for installationinto an air filter housing (11), comprising: an filter body (16) of afilter medium (18), the filter body having an oncoming flow side (28)where fluid to be filtered enters the filter element; and an outgoingflow side (30) where fluid to be filtered exits the filter element anddefining an element axis (14) extending through the filter element fromthe oncoming flow side (28) to the outgoing flow side (30), wherein, asused herein, axial is a direction parallel to the element axis andradial is a direction transverse to the element axis; the filter bodycomprising a plurality of radially outer longitudinal surfaces (24) ofthe filter body (16), the plurality of radially outer longitudinalsurfaces extending axially from the oncoming flow side (28) of thefilter body (16) to the outgoing flow side (30) of the filter body (16);wherein the filter element comprises: a first end disk (32) disposed onand connected to a first radially outer longitudinal surface of theplurality of radially outer longitudinal surfaces of the filterbody(16), the first end disk arranged between the oncoming flow side(28) and the outgoing flow side (30); wherein the plurality of radiallyouter longitudinal surfaces of the filter body (16) include a pair ofradially opposing outer longitudinal surfaces consisting of: a radiallyopposing outer longitudinal surface arranged at a first edge of thefirst radially outer longitudinal surface of the filter body (16); and asecond opposing outer longitudinal surface of the filter body (16)arranged at an opposite second edge of the first radially outerlongitudinal surface of the filter body (16); at least one longitudinalretaining configuration (38) connected to and extending axially across aradially outer surface of the first end disk, having: at least onelongitudinal retaining surface (40) extending axially across a radiallyouter surface of the first end disk, wherein the at least onelongitudinal retaining surface (40) is adapted to contact acorresponding longitudinal mating surface of the filter housing (11)when in an installed state in the filter housing, the at least onelongitudinal retaining surface (40) supporting the filter element (10)in position axially; and a traverse retaining configuration (46)connected to the first end disk (32) and spaced axially away from the atleast one longitudinal retaining configuration (38), the traverseretaining configuration (46) including: at least one transverseretaining fork (250), each have a first leg (52) and a second leg (52),the first and second legs spaced apart in a radial direction transverseto the element axis forming a gap therebetween, the first leg (52) andthe second leg (52) projecting radially outwardly from the first enddisk, wherein the at least one transverse retaining fork is configuredto receive and engage a transverse retaining receptacle (54) of thefilter housing into the gap between the first and second legs, whereinin the installed state, the at least one retaining fork (250) fixes aposition of the filter element (10) in the housing (11) in a directiontraverse to the element axis (14).
 2. The filter element according toclaim 1, wherein the at least one transverse retaining fork (250) isspaced away from the at least one longitudinal retaining surface (40) inan axial direction.
 3. The filter element according to claim 1, whereinthe at least one transverse retaining fork (250) has a portion that isof an elastically deformable material such that the first end the secondlegs are variable elastically in position relative to the filter body(16).
 4. The filter element according to claim 1, wherein at least oneof the transverse retaining fork (250) and at least one of thelongitudinal retaining surfaces (40) is disposed in the proximate toopposing end sides (28, 30) of the filter element (10) axially withrespect to the element axis (14), in the installation direction (12). 5.The filter element according to claim 1, wherein the at least onelongitudinal retaining configuration with the at least one of thetransverse retaining fork (250) is formed on and together with the atleast one end disk (32) as a one piece unitary component.
 6. The filterelement according to claim 1, wherein the at least one longitudinalretaining configuration extends circumferentially and closes around thefilter body on peripheral sides of the filter body.
 7. The filterelement according to claim 1, wherein the first and second legs (52) ofthe at least one retaining fork (250) have a first end fixed to an outersurface of the first end disk (32) and projecting radially outwardlyaway from the filter body.
 8. An air filter for filtering a fluid,comprising: a filter housing (11), including at least one inlet for thefluid; and at least one outlet for the fluid; at least one filterelement (10) according to claim 1, wherein the at least one filterelement is a flat filter element having open filter body (16) made of afilter medium (18) which has an oncoming flow side (28) and an outgoingflow side (30) for the fluid to be filtered; wherein the at least onefilter element (10) is disposed inside the filter housing (11) andseparates the at least one inlet from the at least one outlet; whereinthe filter housing further includes at least one transverse retainingreceptacle (54) provided in an inner wall of the filter housing, the atleast one transverse retaining receptacle received into the gap betweenthe first and second legs and engaging with the at least one retainingfork of the filter element, fixing a position of the filter element (10)in the filter housing (11) in a direction traverse to the element axis(14); a corresponding longitudinal mating surface against which the atleast one longitudinal retaining surface (40) of the filter elementcontacts, which is directed with at least one direction componentaxially to an element axis (14) of the filter element (10) and which isin contacts, retaining the filter element (10) axially in the filterhousing.
 9. A filter housing (11) of a filter for fluid, which has atleast one inlet and at least one outlet for fluid and in which at leastone filter element (10) according to claim 1 is installed, wherein thefilter element is a flat filter element, is disposed and separates theat least one inlet from the at least one outlet; and wherein the filterhousing (11) has at least one longitudinal mating surface with respectto a housing axis (14), said mating surface being directed with at leastone direction component axially to the housing axis (14) and adapted tocontact a corresponding longitudinal mating surface (40) of the filterelement (10) for securing the filter element (10) axially to the housingaxis (14); wherein the filter housing (11) comprises at least onetransverse mating surface (56) which is directed with at least onedirection component transversely to the housing axis (14) which isseparated from the at least one longitudinal mating surface, the atleast one transverse mating surface (56) adapted to contact with acorresponding transverse mating surface (52) of the filter element (10)for securing the filter element (10) across the housing axis (14). 10.The filter element according to claim 1, wherein the at least onetransverse retaining fork (250),is at least two transverse retainingforks (250); wherein a first transverse retaining fork (250) of the atleast two transverse retaining forks (250) is arranged proximate to thefirst edge of the first radially outer longitudinal surface of thefilter body (16) and spaced further away from the opposite second edgeof the first radially outer longitudinal surface of the filter body(16); wherein a second transverse retaining fork (250) of the at leasttwo transverse retaining forks (250) is arranged proximate to theopposite second edge of the first radially outer longitudinal surface ofthe filter body (16) and spaced further away from the first edge of thefirst radially outer longitudinal surface of the filter body (16).